According to a large study of more than seven million people, taking the drug sildenafil (better known under the brand name Viagra) is linked to a lower risk of nearly 70% of developing Alzheimer's disease compared to non-users. This work is published in the journal Nature Aging.
This isn't the first time the use of sildenafil (or Viagra) has been linked to better health outcomes. This drug, usually used for the treatment of erectile dysfunction and pulmonary hypertension, has already shown itself in the fight against cancer and malaria .
In this work led by Dr. Feixiong Cheng of the Cleveland Clinic, researchers began by using computer techniques to map genetic factors that may govern the manifestation of Alzheimer's disease. The researchers particularly focused on amyloid plaques and the tau proteins that we know are involved in the development of Alzheimer's disease.
Furthermore, remember that in previous experiments focused on human brain cells in vitro, researchers had already observed that neurons treated with the drug sildenafil exhibited growth high and reduced tau accumulation .
At the end of their analysis, the authors identified thirteen of these modules. With that data in hand, they then looked at what kinds of FDA-approved drugs could hypothetically help against the identified phenotypes. On more than 1,600 of these drugs , sildenafil turned out to be one of the most promising candidates.
Health insurance data then confirmed these findings. Based on an analysis of health insurance claim data involving over 7.2 million people , the team found that sildenafil users had a 69% reduced risk of developing Alzheimer's disease compared to non-users, especially in people with coronary heart disease, hypertension and type 2 diabetes.
It is important to note that this is only an association and not a proven cause and effect link. For example, it is possible that people in the cohort who took Viagra benefited from other factors limiting their increased chances of not developing Alzheimer's disease. These include the practice of sport or a better quality of sleep, among other possibilities.
Nevertheless, the researchers claim that the correlation shown here is large enough to identify sildenafil as a promising drug candidate for Alzheimer's disease. Its viability could therefore be explored in future randomized clinical trials.
